Answer:
When is 1500 plus 20 and 1600 minus 40 the same thing?
I'm a green veggie that looks like a tiny tree.
This type of corn swells up and bursts into a crisp puff when heated.
There is an ancient invention still used in some parts of the world today that allows people to see through walls. What is it?
You can have it, and be at it, But it never lasts forever.
I am the fountain from which no one can drink. For many I am considered a necessary link. Like gold to all I am sought for, but my continued death brings wealth for all to want more.